// Хранилище данных (localStorage + экспорт/импорт)
const DB_VERSION = 1;

const defaultData = {
  employees: [],
  decrees: [],
  payments: [],
  currentPeriod: '2026-08',
  operations: []
};

let db = loadData();

function loadData() {
  try {
    const saved = localStorage.getItem('executive_sheets_db');
    if (saved) {
      const parsed = JSON.parse(saved);
      return { ...defaultData, ...parsed };
    }
  } catch (e) {
    console.error('Ошибка загрузки данных:', e);
  }
  return { ...defaultData };
}

function saveData() {
  try {
    localStorage.setItem('executive_sheets_db', JSON.stringify(db));
  } catch (e) {
    console.error('Ошибка сохранения данных:', e);
    showToast('Ошибка сохранения данных', 'error');
  }
}

function addEmployee(emp) {
  const existing = db.employees.find(e => e.tabNum === emp.tabNum);
  if (existing) {
    existing.name = emp.name;
    existing.iin = emp.iin;
    existing.salary = parseFloat(emp.salary) || 0;
    existing.updatedAt = new Date().toISOString();
  } else {
    db.employees.push({
      ...emp,
      id: Date.now(),
      salary: parseFloat(emp.salary) || 0,
      createdAt: new Date().toISOString(),
      updatedAt: new Date().toISOString()
    });
  }
  saveData();
  logOperation('employee', 'create', `Сотрудник ${emp.name} (таб. ${emp.tabNum})`);
}

function updateEmployee(id, updates) {
  const emp = db.employees.find(e => e.id === id);
  if (emp) {
    Object.assign(emp, updates);
    emp.updatedAt = new Date().toISOString();
    saveData();
    logOperation('employee', 'update', `Сотрудник ${emp.name}`);
  }
}

function deleteEmployee(id) {
  const idx = db.employees.findIndex(e => e.id === id);
  if (idx !== -1) {
    const name = db.employees[idx].name;
    db.employees.splice(idx, 1);
    saveData();
    logOperation('employee', 'delete', `Сотрудник ${name}`);
  }
}

function addDecree(decree) {
  decree.id = Date.now();
  decree.status = 'active';
  decree.paidAmount = 0;
  decree.createdAt = new Date().toISOString();
  db.decrees.push(decree);
  saveData();
  logOperation('decree', 'create', `Постановление ${decree.number}`);
}

function updateDecree(id, updates) {
  const d = db.decrees.find(d => d.id === id);
  if (d) {
    Object.assign(d, updates);
    d.updatedAt = new Date().toISOString();
    saveData();
    logOperation('decree', 'update', `Постановление ${d.number}`);
  }
}

function deleteDecree(id) {
  const idx = db.decrees.findIndex(d => d.id === id);
  if (idx !== -1) {
    const num = db.decrees[idx].number;
    db.decrees.splice(idx, 1);
    saveData();
    logOperation('decree', 'delete', `Постановление ${num}`);
  }
}

function addPayment(payment) {
  payment.id = Date.now();
  payment.status = 'processed';
  payment.createdAt = new Date().toISOString();
  db.payments.push(payment);
  
  const decree = db.decrees.find(d => d.id === payment.decreeId);
  if (decree) {
    decree.paidAmount = (decree.paidAmount || 0) + parseFloat(payment.amount);
    if (decree.paidAmount >= decree.amount) {
      decree.status = 'closed';
    }
    saveData();
  }
  logOperation('payment', 'create', `Выплата по ${payment.decreeNumber}`);
}

function getEmployees() {
  return db.employees;
}

function getDecrees(filter = 'all') {
  if (filter === 'all') return db.decrees;
  if (filter === 'alimony') return db.decrees.filter(d => d.type === 'alimony');
  if (filter === 'other') return db.decrees.filter(d => d.type === 'other');
  if (filter === 'closed') return db.decrees.filter(d => d.status === 'closed');
  return db.decrees;
}

function getDecreesForEmployee(empId) {
  return db.decrees.filter(d => d.employeeId === empId && d.status === 'active');
}

function getPayments() {
  return db.payments;
}

function getCurrentPeriod() {
  return db.currentPeriod;
}

function setCurrentPeriod(period) {
  db.currentPeriod = period;
  saveData();
}

function logOperation(type, action, description) {
  db.operations.unshift({
    id: Date.now(),
    type,
    action,
    description,
    timestamp: new Date().toISOString()
  });
  if (db.operations.length > 100) {
    db.operations = db.operations.slice(0, 100);
  }
  saveData();
}

function getRecentOperations(limit = 5) {
  return db.operations.slice(0, limit);
}

function getStats() {
  const activeDecrees = db.decrees.filter(d => d.status === 'active');
  const totalDebt = activeDecrees.reduce((sum, d) => sum + (d.amount - (d.paidAmount || 0)), 0);
  const currentPeriod = getCurrentPeriod();
  const paidThisMonth = db.payments
    .filter(p => p.period === currentPeriod)
    .reduce((sum, p) => sum + parseFloat(p.amount), 0);
  
  return {
    employees: db.employees.length,
    activeDecrees: activeDecrees.length,
    totalDebt,
    paidThisMonth,
    closedDecrees: db.decrees.filter(d => d.status === 'closed').length
  };
}

function calculateDeductionsForEmployee(employee) {
  const decrees = getDecreesForEmployee(employee.id);
  if (decrees.length === 0) return null;
  
  const maxDeduction = employee.salary * 0.5;
  const alimonyDecrees = decrees.filter(d => d.type === 'alimony');
  const otherDecrees = decrees.filter(d => d.type === 'other');
  
  let totalAllocated = 0;
  const allocation = [];
  
  alimonyDecrees.forEach(d => {
    const remaining = d.amount - (d.paidAmount || 0);
    allocation.push({
      decree: d,
      allocated: Math.min(remaining, maxDeduction * 0.5)
    });
    totalAllocated += allocation[allocation.length - 1].allocated;
  });
  
  const remainingForOther = maxDeduction - totalAllocated;
  if (remainingForOther > 0 && otherDecrees.length > 0) {
    const perOther = remainingForOther / otherDecrees.length;
    otherDecrees.forEach(d => {
      const remaining = d.amount - (d.paidAmount || 0);
      allocation.push({
        decree: d,
        allocated: Math.min(remaining, perOther)
      });
    });
  }
  
  return {
    employee,
    maxDeduction,
    allocation,
    totalAllocated,
    remaining: employee.salary - maxDeduction
  };
}

function exportToCSV(data, filename) {
  if (!data || data.length === 0) {
    showToast('Нет данных для экспорта', 'error');
    return;
  }
  
  const headers = Object.keys(data[0]);
  const csv = [
    headers.join(';'),
    ...data.map(row => 
      headers.map(h => {
        const val = row[h] !== null && row[h] !== undefined ? String(row[h]) : '';
        return '"' + val.replace(/"/g, '""') + '"';
      }).join(';')
    )
  ].join('\n');
  
  const blob = new Blob(['\uFEFF' + csv], { type: 'text/csv;charset=utf-8;' });
  const link = document.createElement('a');
  link.href = URL.createObjectURL(blob);
  link.download = filename;
  link.click();
  showToast('Файл скачан: ' + filename, 'success');
}

function clearAllData() {
  if (confirm('Вы уверены? Все данные будут удалены безвозвратно.')) {
    localStorage.removeItem('executive_sheets_db');
    db = { ...defaultData };
    showToast('Все данные удалены', 'success');
    location.reload();
  }
}